Add breather

[ilandahan]

Adds breather.

What it does: tracks how long the user has actually been present across every Claude Code session on the machine, with idle gaps over 20 minutes removed, and at safe boundaries — tests green, a commit, a question resolved — offers a stopping point with a written handoff, so the context does not die with the session.

Why it fits this list: it improves the experience of Claude Code itself and requires no external service — no API to call, no account, no server of mine in the path. One file, Node stdlib only, nothing fetched at runtime.

Checklist

• MIT licensed
• SKILL.md with name and description frontmatter at skills/breather/SKILL.md
• Installable as a Claude Code plugin; claude plugin validate passes
• No dependencies, no telemetry, no network calls at runtime
• Installer behaviour covered by tests against a throwaway home; CI on Linux, macOS and Windows
• One entry added, existing section formatting and alphabetical order followed